Savoia-Marchetti S.64

Savoia-Marchetti

Company type	Aircraft manufacturer
Industry	Aerospace
Founded	1920s
Headquarters	Italy

The Savoia-Marchetti S.64 was a sizable monoplane created and produced by the Italian firm Savoia-Marchetti. Its design in the late 1920s aimed specifically at challenging global endurance and distance flight records.

The development process of the S.64 was shrouded in considerable confidentiality. Its inaugural flight took place on 3 April 1928, piloted by Alessandro Passeleva alongside Carlo Del Prete. Initial trials occurred at Montecelio, marking it as one of Italy’s pioneer aircraft to utilize a concrete airstrip. On 31 May 1928, the duo of Arturo Ferrarin and Carlo Del Prete achieved three world records by completing 51 laps between Torre Flavia (near Ladispoli) and Anzio.

Design

The S.64 was engineered as a large monoplane tailored for extended-range flights. Achieving such endurance required an exceptionally streamlined form, minimizing all structural resistances through the use of aerodynamic fairings and careful shaping—efforts supported by comprehensive wind tunnel assessments of scale models. The wing design avoided elements prone to creating turbulence or drag, resulting in a clean aerodynamic profile. The aircraft employed an uncommon pod-and-boom structure, with its tail assembly mounted on two open truss frameworks extending aft from the wings, reminiscent of the earlier Savoia-Marchetti S.55. The fully enclosed cockpit was situated within the compact fuselage pod.

Its wing was a cantilever, single-piece wooden structure, relatively thick at the center tapering towards the tips. Internally, it was segmented into multiple watertight compartments to ensure buoyancy if forced to land on water. The wing’s framework consisted of three spars. A pair of girders connected the wing to the horizontal stabilizer; the upper girder incorporated a robust duralumin tube embedded within the wing, while the lower girder ended forward in a forked shape supporting the landing gear. The undercarriage itself was straightforward, featuring two sets of vertical struts and a split axle with wheels mounted on ball bearings and enclosed within streamlined fairings. Each girder also carried a tail skid that pilots could adjust to either dig into or slide over the ground, aiding in controlling takeoff run initiation.

Power was supplied by a single Fiat A.22T V-12 water-cooled piston engine delivering up to 550 horsepower at 1,900 rpm, mounted atop cabane struts above the wing in a pusher configuration with a pointed spinner on its propeller hub. This isolated placement minimized airflow interference, achieving a high propeller efficiency estimated at 0.8. The engine cylinders remained exposed without cowling, exhausting gases directly into the atmosphere rather than through pipes. Honeycomb-style radiators were positioned beneath and behind the wing’s central section; these could be extended or retracted for temperature regulation. The engine rested on a lightweight frame, transmitting thrust via two long oblique struts, while its elevated mounting necessitated an advanced tail skid design to balance ground handling.

Fuel capacity was distributed across 27 duralumin tanks holding approximately 7,000 liters (1,849 gallons), occupying nearly three-quarters of the wing’s length. Fuel flowed from these tanks into a central reservoir before being pumped to the engine; an auxiliary manual pump provided backup if needed. A secondary fuel line served as a contingency for primary pipe failure, an approach previously utilized on the Junkers G 31. Emergency fuel jettison capability was also incorporated. Crew members actively managed fuel distribution using various valves and pumps to maintain optimal center of gravity throughout flight. Oil was stored in a 270-liter (71-gallon) tank divided by two transverse bulkheads and mounted ahead of the engine support frame; part of this tank was exposed to airflow for cooling purposes. The pilot controlled oil temperature by adjusting hot and cold oil flow rates based on readings from remote thermometers.

The S.64 came equipped with several instruments and devices: radio equipment capable of transmissions exceeding 500 km (311 miles), a powerful searchlight mounted forward on the nacelle for nighttime landings, and navigation tools including three compasses (two magnetic and one earth-inductor type), gyroscopic indicators monitoring pitch, roll, and yaw stability, plus two sextants for celestial navigation. Multiple openings across different wing sections accommodated these instruments’ sensors and probes; Venturi tubes and an airspeed indicator windmill were positioned ahead of the nacelle to measure airspeed accurately.

Record flights

On 31 May 1928, Arturo Ferrarin and Carlo Del Prete established three global records in the S.64 by completing 51 circuits between Torre Flavia (located in Ladispoli) and Anzio. Upon landing on 3 June, they had flown a total of 7,666 km (4,791 mi), setting a new world distance record for a closed loop, and remained airborne for 58 hours and 34 minutes, achieving a new endurance record. Additionally, they established the world speed record over a 5,000 km (3,110 mi) stretch at an average velocity of 139 km/h (87 mph). Following the successful record attempt, it was announced that this mission served as preparation for a future transatlantic flight from Rome to New York City.

The subsequent month, Ferrarin and Del Prete indeed undertook a transatlantic journey in the S.64, although their destination was not New York but Brazil across the South Atlantic. They departed from Montecelio on the evening of 3 July, flying overnight over Sardinia and reaching Gibraltar early the following day. On 4 July, their route took them past Casablanca and Villa Cisneros, and by nightfall they were over the Cape Verde archipelago en route to Brazil. By the morning of 5 July, they were within radio contact range of Pernambuco. Crossing the Brazilian coastline near Natal, they proceeded southwards aiming for Rio de Janeiro. However, adverse weather conditions compelled them to turn back toward Natal. With fuel reserves dwindling and weather still unfavorable, they could not land at Natal either due to the airfield being situated behind hills. Consequently, they continued northward for approximately 160 km (100 mi) before executing an emergency landing on a beach at Touros. A Brazilian mail aircraft transported Ferrarin and Del Prete first to Natal and subsequently to Rio de Janeiro, where both cities greeted them as heroes. The S.64 sustained structural damage during its sandy beach landing and was shipped to Rio de Janeiro. Upon arrival, the aircraft was donated to Brazil. Throughout this flight from Italy, the S.64 covered 8,100 km (5,030 mi) over 48 hours and 14 minutes. The FAI officially recognized this as a flight covering 7,188 km (4,500 mi)—the orthodromic distance between Montecelio and Natal—setting a new world record for straight-line distance. Celebrations in Rio de Janeiro lasted several weeks but ended tragically when Ferrarin and Del Prete crashed during a demonstration flight in a S.62 on 11 August. Del Prete succumbed to his injuries five days later.

S.64bis

In 1930, an enhanced version of the S.64, known as the S.64bis, was introduced with the goal of reclaiming the duration and closed-circuit distance records that had been surpassed since the flight of Ferrarin and Del Prete. From 30 May to 2 June, Umberto Maddalena and Fausto Cecconi completed a closed-circuit flight starting from Montecelio, covering a distance of 8,188 km (5,088 mi) over a span of 67 hours and 14 minutes, thereby setting new benchmarks for both distance and flight duration. They were preparing to make another attempt at the endurance record using the S.64bis when, on 19 March 1931, the aircraft crashed into the sea near Pisa. Tragically, Maddalena, Cecconi, and their mechanic Giuseppe Da Monte lost their lives in the accident. The debris was scattered extensively, preventing a definitive determination of the crash's cause, although the Inquiry Commission suspected a failure in the crankshaft, which might have led to the propeller damaging several parts of the airplane.

The legacy of Ferrarin, Del Prete, and the S.64 is honored in Rio de Janeiro at Praça Carlo Del Prete, where a statue of Del Prete stands alongside a bronze model of the aircraft at half scale.

Specifications (S.64)

Bibliography

• "Savoia Marchetti "S 64" Airplane" National Advisory Committee for Aeronautics, 1 August 1928. NACA-AC-78, 93R19961.